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estimatcd at 10,000 cfs. The highest snowmclt pcak at Dolores, 8,070 cfs, was rccorded in May 1941. In June 1949 a general rain on the snowpack produced an even higher peak al Dolores, 8.140 cfs. For the SO years of rccord at the Rico gage, the highest snowmelt peak, 2,170 cfs, was rccorded May 1984; the highest raintlood peak, 1,930 cfs, rccorded September 1970. Most of the annual rainllood peaks were small events. Due to the scarcity of large rainllood peaks. the rain on snow events \\:erc included in the record for analysis. 8.3 Flood Frequency Analysis. The BEe Flood Frequency Analysis (FFA) computer program (see Referencc 4-k) was used to apply Water Resource Council Guidelines to the statistical analysis (Sce Reference -l-m). The annual snowmelt and rainl100d duration data werc analyzed scparate1y using the FFA program. The sno\l..'melt flows for Dolores River at Dolorcs were analyzcd for peak, 14,34,74, IS-, 30-, 60-, and 90-day durations. For Dolorcs Rivcr below Rico gage, the snowmelt scason is shorter; the 60- and 90-day durations \I,.'ere not considered. The rainllood tlows \"'cre analyzed for the 1_.34.74, IS-, and 30-day durations. since the impact of rain on snowpack runolT does not last longer than a month. Too many annual raintlood peak flows are missing from the records for Rico and Dolores to allow for any meaningful statistical analysis. so Ihe FFA program was not used for the rainllood peaks. The FF A program did not identify any high or low outlier rainlloods for the Rico and Dolores gages. For the sno\\'Tllell records, FFA analysis identified 1977 and 2002 as low outlier years at both Rico and Dolores; 1990 and 2002 wcre low outlier years at the Lost Canyon Creek gage. The annual tlow duration data for Rico and Dolores wcre analyzed as database sets for rain flood and snowmelt scparatcly for each gage. The I-IEe-Regional Frequency Computation Program (REGFQ. see Reference 440 was used to analyze the duration data sets, to smooth the 31